System of control



April 15 1924. 490,198

Q. A. BRACKETT SYSTEM OF CONTROL Filed Jan; 24, 1921 INVENTOR Qu/hcyA 5/6 BY a. I

Patented Apr. 15, 1924.

T barren STATES 1 means "PATENTZV'VOFFICE.

QUINCY A. BRACKETT, or PITTSBURGH, mnnsynvnnm, essreno n To WESTING- HOUSE ELECTRIC VNIA,

&. MANUFACTURING- .VC0MIEANY, a coaronaTronor runner];-

' SYSTEM or CONTROL. I Q

7 Application filed January 24 1921. Serial No. 439,391. I

To all whom it may concern:

Be'it known that LQUINQY A. Bnnoxn'rr,

mam ofthe United States, and a resident of Pittsburgh, in the county of Allegheny and Statef'o'f Pennsylvania, have invented a trolling the radiation of electrical energy in the of deem-ma netic waves.

object of my invention is to provide means whereby the radiation. of energy from. an." antenna. circuit of a wireless-transmission systemmay be selectively controlled by means of an absorbing, non-radiating circuit operatively coupled" to the antenna circuit; 5

The, present systems 'ofcontrol suitable for high-power, high-frequency generator systems employ cont-rolling circuits which are connected in shunt relation to. the source similar'modulat'ions in the energy supplied {to the antenna circuit.

The particular disadvantage-of the pres-' ent'systems of control, however, are the continuous radiation of energydur ng the nonsignaling period and the radiation of energy at two wave lengths during the signaling period; V f f According to my invention, 1 provide means which permits of the radiation of energy atone wave length. during the signaling period and effectually renders the radiating system non-efiective during the' absorbing circuit 6. An electromagnet de non-signalingperiod.

The desired. result is accomplished by By varying either the capacitance or inductancef'of the absorbing or non-radiating circuit, it may be selectively rendered reso .nant or non-resonant to the generator fre quency, to selectively controlthe radiation of energy from the antenna circuit,

My invention may best be understood byreference to the I accompanying drawings, 1n which: 1

my invention. Figs. 2, 3, 4 and 5 are simllar views showing alternate arrangementsto' that of Fig llre ' Like numerals are employed to designate like parts having similar functions.

Referring to Figure 1, a source of energy 1 is operatively connected to a radiating.

circuit through coupling coilsg2 and=3, respectively. The radiating circuit includes an ntenna .4, the coupling coil 3 anda ground lead 5;

An absorbing circuit 6 is operatively con nected were radiatingcircuit and the supply circuit through a coupling coil 7' and coupling coils 3 and 2, respectively. This circuit comprises the coupling transformer 7,'an inductor 8, apair'of condensers 9 and 11, a key 12 for'shuntin'g' condenser 11 and an adjustable resistor 13. r

Figure 1 is a diagrammatic representa 'tion of circuitsand apparatus embodying The arrangement shown in Fig. 2 di ffersfrom that of Figureilin the. parallel connection of a pair of condensers 14 and 15 in the absorbing circuit 6. The key 12 is connected in series with the condenser 14. "The capacitance of. condenser 14 is small, in comparison with that of condenser 15. g p I The arrangement shown in'Fig. 3 differs from those of Figs. 1 and 2 inthat the period of the absorbingcircuit 6 may be varied by. shunting a portion of the inductor 8 by means of the key 12.

Referring to Fig. 4, the arrangement shown diifersfrom that of 3' in that theinductance of thelcircuit is controlled by varying the magnetic flux through a pair ofcoils 16 and 17 which are included in the vice 18, which may be employed to effect the desired changes in the period of the absorbing circuit, comprises a pair of cores 19 and 21, together with the magnetizing windings 16 and 17. A third core 22, which circuits through coils 16 and l'T may e Selectively controlled by,msans' of a circuit the'generator' frequency; The 'electromag which comprises a source of energy 24 and the controlling winding 23.

Referring, to Fig. 5, the system here shown differs from those of the previous arrangements in that means are provided for simultaneously tuning the absorbing circuit and detuning the antenna circuit wlthrespect to netic device 18 is similar in construction to cuits is also similar toithat of lllig. 4,. with the exception that the magnetizing Winding 17is included in theantenna, circuit. The constants of the antenna and absorbing circuit are ,so adjusted that, with the..key 12 is .detuned. V

In the operation. of my system, with. the j absorbing circuit in resonance with the highfrequency alternating currents .l trayersing the ant circuit the eneigy v absorbed therefroinl is a manirnum.

Referrin to ;Fi'g., l, with;the-. key

tially an get the powersu of my invention, it is still capable of various changes and modifications within the scope of theappended claim s. I desire, therefore, that only such'limitations shall be imposed thereon as are indicated in the appended claims. q g V I claim as my invention: I H

1; Ina wireless transmission system, the

f {,1 combination with a supply circuit and a rathat of Fig. 4:. The arrangement'of the cir-' .erativelyaassociated with said supply cirsorbingl circuit also. including a coihanda cuit, magnetic means interlinking said radiating ClICllliLitIldSfild absorbing ClIGIllb and means s operating on the magnetic characteristics of said: magnetic: means for subopen, the absorbing circuitistuned to the generator frequency and the antenna circuit diating -r circuit effective and i said abs orbing-i circuit inon;effectiya: andvice'; versa,

2." i In, a in wireless transmission a system, the combination with a supply circuitsand a radiatingcircuit including .a' coil, of an abreat v l um d; 1 ith=sa d Prr1r i tenna circuit to'be' absor edrby; thegnonradiating .absorbing ;circuit.

Up on 'closing the key v 12,1 the nondenser 11 radiation from" the antenna.-

cuit, a magnetic .coreginterconnecting said rad ating and ,;ab sorb1ng circu t, r co ls; and mea for v ry t m gnet c ch ract ri tics 35f, Said: core; whereby saidradiating and;

b crbinga ita may a be sel ct vely 1 said. idling. circuit being operatively asso. cia ted flwithlsaid supp y 0ireuit, coils indi- The operation-of the arrangements shown I: in Figs..2, 3 and lis substantially,lthe same as that of Fig. 1. Thedifierence'tbetweenthe systems shown, inthe several figures .con-

sists' ini thev utilization of, various1,key;contr01led,mea'ns for efiecting changes' vin the period of theiahsorbing, circuit.

Referring, to- Fig. i 5; with :constants of the antenna and absorption circuits soadjusted r ergy is radiated by the antenna circuits The energy that-is absorbed bythe non-radiating circuit may be dissipated asih eat inithe' resistor .13.

is shunted to detunev the F absorption circuit thereb permittingvar maximum amount 0 3 'In i combination; a work circuit," a supply circuit therefor, and an idling circuit,

vidual to,.\ said..work circuit and to said absorbing circuit ;.a :Inagnetizable core for said coils,\and.modulatingineans for varying-the magnetic characteristics of saidcorel 4 The combination withasource'of oscillator y "currents; of g a tuneda Workcircuit, a tuned. absorbing, circuit operatively. associated with said ,source, tuning; .coils individual to said work van d absorbingcircuits, a magnetizable yoke member for saidcoils, a

modulating magnetizing coil for said -yoke member, and. a modulatingrcircuit operatively I associated with said last-mentioned coil, vhereby said work circuit maybe rendefied-t. effect ve and ,said \absorbingcircuit duced by the magnetizingvwinding ;23:s0 ,varies the permeability of [the magnetic circuits through the coils l6 and ,17Ithat 1theaan- The- ,p articular; advantage :of; L arrangementjis in'the provision of a slmple;; inexpensiye control system 1 g or l ;.selectivel -y .controlling the radiation 'of ener wh l i erei Jawarenes u t en i vicejyei 'fromian antenna.;o f al wireles transm-i si on isystemg non-efi'ective; and vice Versa;

5,..In'a radioisignaling system' emp loying oscillatory. currents, a tuned 'work circuit including, energyt'ranslatinglmeans, av tuned idling circuit including ,means. for producingvfthe efiect iof -ia resistance having-a .desired relation to that ofsaid energyatranslating means, tuning coils individual .to"; said c rcuits, a. common magnetizable yoke- ,inerne ber.-foi said ..tuning coils; and, a modulating magnqtizijrig coil also associatedlwith said yok membernpereble t r m a wor cirtordetunesaid lidling circuit, and

. i 65, The combinat on. w th a sourcev of oscillatory currents one, tunedifworkgcircuit te-Basile a teaai ne ytranslating means included in said work circuit, a tuned auxiliary circuitalso adapted to be connected to said source, coils individual to said work and auxiliary circuits, an iron core transformer having a plurality of individual core portions to provide one for each coil, and an auxiliary winding adapted to serve as modulating means operable to oppositely vary the tuning of said circuits.

7. The combination with a source of 0scillatory currents, of a tuned work circuit adapted to be connected thereto, energy translating means included in said work 011- cuit, a tuned auxiliary circuit also adapted to be connected to said source, coils individual to said work and auxiliary circuits, a modulating coil, an iron core transformer having a plurality of individual core portions to provide one for each coil, and a modulating circuit for said modulating winding, whereby said work circuit may be detuned and said auxiliary circuit tuned, and vice versa.

In testimony whereof, I have hereunto subscribed my name this 14th day of J anuar 1921. QUINCY A. BRACKETT. 

